Detergent compositions for laundering



United States Patent 1 2,805,205 DETERGENT COMPOSITIONS FOR LAUNDERING TEXTILE FABRICS, CONTAINING A COPOLY- MER 0F ACRYLONITRILE AND AN ACRYL- AMIDE George P. Touey and Harry W. Coover, Jr., Kingsport,

Tenn., assignors to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey N0 Drawing. Application February 11, 1953, Serial No. 336,442 3 Ciaims. (Cl. 252152) This invention relates to detergent compositions for the laundering of textile fabrics. More particularly, it relates to detergent compositions which not only remove soil from textile fabrics, but prevent redeposition of the soil on the fabrics during the laundering operations.

In the wet laundering of textile fabrics, the effectiveness of the detergency action is dependent upon two factors: removal of the soil from the fabric, and prevention of redeposition of the soil on the fabric before the laundering cycle is completed. Synthetic detergents are known to be excellent dispersing and cleaning agents; however, in the laundering of textile fabrics they are incapable of preventing a portion of the removed soil from redepositing on the fabric. In the case of dyed fabrics, the redeposited soil results in a considerable loss of the original brightness. In the case of white fabrics, it prevents restoration of their full whiteness.

A number of substances have been tested as adjuvants in detergent compositions, for preventing soil redeposition. Armstrong et al., American Dyestutf Reporter 37, 596 (1948), have compared polyvinyl alcohol, methyl cellulose, potato dextrin, chrome glue, cornstarch, bentonite, and sodium carboxymethylcellulose in their effectiveness for this purpose. With the exception of sodium carboxyrnethylcellulose, however, none of these substance has found general acceptance in the trade.

Although carboxymethylcellulose is moderately effective for preventing soil redeposition in the laundering of cotton fabrics, it suffers the disadvantages of being ionic in nature, and is readily precipitated by salts of diand polyvalent metals such as calcium, magnesium, zinc, iron and aluminum. It i therefore adversely affected by hard water. Moreover, even in soft water, it does not prevent redeposition of soil in the laundering of cellulose acetate, nylon or wool.

We have discovered that the addition of copolymers of acrylonitrile and an acrylamide selected from the group consisting of acrylamide and the lower alkyl acrylamides to anionic or nonionic detergents prevents redeposition of soil on textile fabrics when the fabrics are washed with these detergents. In the term anionic detergents, we mean to include soap as well as the synthetic anionic detergents.

The copolymers of acrylonitrile and an acrylamide selected from the group consisting of acrylamide and the lower alkyi acrylamides have the general structure The ratio of n to m lies in the range of 1:1 to 20:1; X=5D to 1000; R'=H, CH3, Cal-I5, 0r Cal-I7; R=H, CH3 or CzHs.

These copolymers are conveniently made by the copolymerization of acrylonitrile and the acrylamide in bulk solution or emulsion. The usual polymerization catalysts or initiating agents are used, and certain socalled activating agents such as sodium bisulfite may be used in connection with the catalyst. For example, an interpolymer containing 70% acrylonitrile and 30% N- methylmethacrylamide can be prepared by heating a solution of 7 parts of acrylonitrile, 3 parts of N-methylmethacrylamide, and 0.1 part of potassium persulfate in 40 parts of water at 50 C. for 24 hours. The resulting copolymer is obtained as a clear viscous solution. The polymer can be isolated from the water solution by the addition of a non-solvent or by the evaporation of the water solution.

Our novel detergent compositions are mixtures of copolymers of acrylonitrile and an acrylamide selected from the group consisting of acrylamide and the lower alkyl acrylamides, with a detergent selected from the group consisting of the anionic detergents, including soap, and the non-ionic detergents, in ratios ranging from 1 part copolymer:99 parts detergent to 25 parts copolymer: parts detergent. Although higher proportions of the coplymer can be used, the improvement in the cleaning power was found to reach a maximum at 25 parts copolymerz75 part detergent. Improvement in detergency was noticeable at a ratio of 1 part copolymerz99 parts detergent. However, the most desirable range is from 2 parts copolymerz98 parts detergent to 10 parts copolymerz parts detergent.

Using the following types of detergents, we have found that a mixture of parts by weight of detergent and 5 parts by weight of an acrylonitrile-acrylamide copolymer gives better detergency than parts by weight of the same detergent:

1. An alkyl sulfate (anionic) 2. An alkyl sulfonate (anionic) 3. An alkyl-aryl sulfonate (anionic) 4. A sulfonated amide (anionic) 5. A fatty acid-polyethylene glycol condensate (non ionic) 6. A phenol-polyethylene glycol condensate (non-ionic) 7. An alcoholpolyethylene glycol condensate (non-ionic) 8; A mercaptan-polyethylene glycol condensate (nonionic) 9. A polypropylene glycol-polyethylene glycol condensate (non-ionic) l0. Soap (anionic) The improvement obtained by the substitution of the acrylonitrile-acrylamide copolymers for a portion of a detergent (or detergent-builder combination) varies according to the efiiciency of the original detergent formulation. For example, by means of these copolymers it is possible to improve anionic type synthetic detergents to the point where they are equal or superior to soap in their ability to prevent soil redeposition during the laundering of textile fabrics. These copolymers also improve soap alone or soap-alkaline builder formulations. In general, therefore, it can be said that by the substitution of these acrylonitrile-acrylarnide copolymers for a small portion of a detergent formulation in which the detergent is selected from the group consisting of the anionic detergents, including soap, and the non-ionic detergents, a remarkable improvement is obtained in the ability of the detergent formulation to prevent soil redeposition.

The mechanism by which these copolymers function as detergent adjuvants is still to be determined. One possible explanation is that the copolymers are selectively adsorbed on the fabric, building a charge that repels the dirt particles after they have once been removed from the fabric. Another explanation is that the copolymers function as soil-suspending agents. Although these copolymers have soil-suspending properties, this mode of action cannot be considered to be the only explanation of their ability to prevent soil redeposition. A large number of water-soluble polymers are known to be excellent suspending agents, yet do not possess the detergency properties exhibited by either sodium carboxymethylcellulose or the copolymers herein described. This is shown by the following example.

EXAMPLE 1 A detergent solution containing suspended carbon soil was prepared by dispersing 14 grams of Aquablak-B (a 35% aqueous suspension of carbon black, manufactured by Binney & Smith Company, New York, N. Y.) in 11 liters of water containing 25 grams of Igepon T (a sulfonated amide, anionic type detergent, having the formula C1rH3aCON(CI-Ia)C2H4SOsNa). Several 100- ml. portions of this stock solution were removed, and to all but one (control) of these portions there was added 0.0125 g. of a water-soluble polymer selected from the list shown in the table below. Thus the weight of adjuvant was approximately of the weight of detergent, in each sample. The solutions were transferred to standard Launder O-Meter bottles (pint size), each containing steel balls, A" in diameter. The bottles of detergent-soil solutions were preheated to 140 F., and a 2 /2" x 3%" piece of clean cotton broadcloth was placed in each bottle. The bottles were sealed and tumbled for 30 minutes at 140 F. in an Atlas Launder- O-Meter. The cloth samples were then removed from the soil solutions, rinsed in warm water, and dried. Reflectance curves were obtained for each washed cloth sample by means of a General Electric recording spectrophotometer. The average percent reflectance values were calculated for the curves. These values were then converted to percent whiteness retained" by means of the following formula:

Percent whiteness retained= X 100 Rw=average reflectance of the cloth laundered in the soil solution. Ro=reflectance of the white broadcloth before laundermg. Table I shows the results of these tests.

Table I [Detergent Igepon T.)

Percent whiteness Adluvant Retained by the Laundered Cloth None 22 Sodium carboxyrnethylcellulose 61 85 N-Methylmethacrylamlde-l5 acrylonitrile copolymer. 67 90 N-Methyimethacrylamide-lO acrylonltrile oopolymer. 68 70 N-Methylmethacrylamide30 aorylonitrile copolyme. 5o Pectin (citrus) 49 Gum arabicm. 45 Mesquite 4 Propylene glycol alginate (Kelcoloid)- 44 Locust bean gum 33 Poly-N-iso propylacrylarnide 35 Poly-N -isopro pylmethacryl amide 31 Methyl cellulose 31 Hydroxyet hylcellulose 30 Sodium salt of polyacrylic acid 25 50 Maleic acid-50 isopropenyl acetate copolymer-Na salt. 25

85 N-Isopropylacrylamide- N-methylaorylamide copolymer Polyviny alcohol (Elvanol) 24 Poly-N-methylacrylamide 23 T2 N-Methylacrylarnide-28 aliyl alcohol copolyrner 21 Dextran (unhydrolyzed) 2(1 70 Acrylic acid acrylonitrile copolymer--Na salt. l8 Poly-N-Methylmethacrylamide 18 40 Acrylic acid-60 N-isopropylacrylamide copolymer-Na l8 l7 s Malelc acid e copolyme Na salt (Sodium Stymer) 12 Sodium alginate (Kelgln) 9 It will be seen that the N-rnethylmethacrylamide-acrylonitrile copolymers gave results averaging as good as those given by sodium carboxymethylcellulose, and better than those given by any of the other adjuvants, in preventing soil deposition.

The following examples illustrates how three detergents EXAMPLE 2 A series of detergent solutions were prepared, having the compositions shown in Table II, so that the total concentration of detergent formulation in each was 0.25%, and the adjuvant portion of the detergent formulation was 0.0125 g., or approximately 5% based on the detergent weight. In 100 ml. of each of the detergent solutions, a 2 /2 X 3 /51" swatch of standard soiled cotton broadcloth (P. S. C. soiled cotton, sold by Foster D. Snell, Inc., New York, N. Y.) was laundered for 30 minutes at 140 F., using an Atlas Launder-O-Meter and 10 steel abrasion balls. The laundered swatches were rinsed in distilled water at 140 F., and the laundering cycle was repeated. After three successive washings the laundered swatches were ironed and dried. Reflectance curves were then obtained for each cloth sample, using a General Electric recording spectrophotometer. This data was converted to percent whiteness regained" values by means of the formulas:

Percent whiteness regained= X 100 u I Rw=Percent reflectance of the soiled swatch after wash- The results are shown in Table II.

Table 11 [Soil removal-Cotton] Determined Formulation (Grams dissolved material in Percent 100 ml. distilled water) whiteness Regained 0.25 g. Igepon 'I (control) 27 0.24 g. Igepon 'I+0.0l25 g. carboxymethyleellulose-Na salt. 35 0.24 g. Igepon T+0.0l25 g. 70 -methylmethacrylamide-3O acrylonitrile 37 0.24 g. Igepon T+0.0125 g. N-methylmethacrylamide-l5 acrylonit 1e 39 0.24 g. Igepon I+0.0l25 g. N-methylmethacryl acrylonitrile 30 0.25 g. Kreelon 40 (control) 22 0.241%. Kreelon 4D+0.0125 g. cerboxymethylcell 32 ea 0.24 g. Kreelon 4D+0.0125 g. 70 N-methylmeth lamlde30 acrylonitrile 32 0.24 g. Kreelon 4D+0.0l25 g. 85 N-methylmethacryl 15 acrylonitrile 35 0.24 g. Kreelon 4D+0.0125 g. 90 N-methylmetha l0 acrylonitrile 34 0.24 g. Duponol ME (control) 29 0.24 g. Duponol ME+0.0125 g. carhoxymethylcellu Na salt 39 0.24 g. Duponol MBA-0.0125 g. 70 N-methylmetha lamide30 aerylcuitrile 37 0.24 g. Duponol ME+0.0125 g. 85 N-methylmethacrylamlde15 aerylonitrile 40 0.24 g. Duponoi ME+0.0125 g. QO-N-methylmethacry- 1arnide-l0 acrylonitrile 41 0.25 g. Ivory soap (control) 39 024mg. Ivory soap+0.(ll25 g. carboxymethylcellulose-Na 48 so 0.24 g. Ivory s0ap+0.0l25 g. 70 Nm'rethylmethitcmlamide- 30 aorylonitrile 47 0.24 g. Ivory soap+0.0125 g. 85 N-methylmethacrylamide 15 acrylonitrile 49 0.24 g. Ivory soap+0.0125 g. 90 N-methylmethacrylamide- 10 acrylonitrile 50 0.25 g. Igepal CA (control) 30 0.24 g. Igepal CA+0.0125 g. carboxymethylcellulose-Na salt. 38 0.24 g. Igepal CA+0.0125 g. 70 N-methylrnethacrylamide- 30 acrylonitrile 36 0.24 g. Igepal OA+0.0125 g. 85 N-methylmethacrylamlde- 1h acrylonitrile 40 0.24 g. Igepal CA+0.0125 g. 90 N-methylmethacrylamide- 10 acrylonltrile 30 Igepon T is e sulfonated amide, anionic type detergent, having the formula CHH CONYCH )C1H S03Na, manufactured by General Dyestufi Corp. Kreelon 4D is a sodium alkylaryl sulfonate type anionic detergent, manufactured by the Wyandotte Chemicals Corp. Duponol ME is a fatty alcohol sulfate anionic detergent (technical sodium lauryl sulfate) manufactured by E. I. du Pont de N emours & 00. Ivory Soap is a sodium soap of vegetable oil fatty acids, manufactured by Procter dz Gamble. Igcpal 0A is a non-ionic polymerized ethylene oxide condensation product (iso-octyl phenoxyethylene ethanol), manufactured by General Dyestufis Corp.

It will be seen that the acrylamide-acrylonitrile copolymers gave results equal to those given by sodium carboxymethyl cellulose, as to soil removal.

Example 3.WHITENESS RETENTION TESTS This example illustrates the ability of the copolymers of N-methyl methacrylamide-acrylonitrile, in which X=600, to prevent wet soil deposition on cotton, nylon, cellulose acetate, and wool.

Clean 2%" x 3%" swatches of cotton, nylon, cellulose acetate, and wool were separately laundered in freshly prepared detergent-soil solutions as listed in Table III. Each solution contained 100 ml. water, 0.25 g. detergent, 0.14 g. Aquablak-B, and 0.0125 g. adjuvant (5% adjuvant based on the weight of detergent), with the exception of the control solutions, which contained no adjuvant. Only one laundering cycle was employed. This was carried out in an Atlas Launder-O-Meter at 110 F., using the standard pint jars and steel abrasion balls in each jar. After a 30-minute treatment, the swatches were removed and separately rinsed in clean water at 110 F. When dry, the samples were ironed.

Reflectance values were obtained for each of the washed and ironed samples by means of a General Electric recording spectrophotometer. These values were substituted in the formula X 100 R0 to obtain the percent whiteness retained" for each cloth sample.

The results are shown in Table III.

Table III [Whitencss rctcntlonCotton, nylon, cellulose acetate, wool] 3 0 Detergent Solution (Grams dissolved Percent material in 100 ml. water) Fabric whiteness Retained 0.25 g. Krcelon 4D (control) Cotton 24 Do Nylon 1.1 Do Cellulose 24 acetate Do Wool 53 0.25 g. Kreelon 4D+0,0125 g. carboxymethyl- Cotton 04 celluloseNa salt.

Do Nylon. 12 Do Cellulose 30 acetate Do Vool 52 0.25 g. Kreelon 4D+0.0i2ti g. 85 N-methyl- Cotton 67 methacrylan11de1 5 nor ylonitrile.

Do Nylon. .t 66 Cellulose 75 V leccltate 80 oo t. Cotton 22 5O Nylo 12 Cellulose 28 acetate Do Wool 56 0.25 g. Nacconol NR+00125 g. carboxymeth- Cotton 61 ylcellulose-Na salt.

Do Nylon"... 14 5 Do Cellulose 37 acetate Do Wool 53 0.25 g. Nacconol NIH-0.0125 g. 85 N met.hyl- Cotton methaerylamidel5 acrylonitrile.

Do Wool 70 0.25 g. Ivory soap+0.0125 g. oarboxymethyl- Cotton 6B 65 oellulose-Na salt.

Do Nylon. 30 Do Cellulose 81 acetate Do Wool 74 0.26 g. Ivory s0ap+00l25 g. 85 N-mcthyl- Cotton 82 methacrylamidei5 acrylonltrile.

Do -r Nylon... 72 Cellulose 89 acetate Do Vool 8B Nacconol NR is an alkyl aryl sodium sulionate anionic detergen manufactured by the National Aniline Division of the Allied Chemica 76 6: Dye Corp.

The nylon cloth used in this example was made of desized, delustered taffeta filament, and was obtained from Test Fabrics, Inc. The cellulose acetate cloth was broadcloth weight, made of plain spun staple. The wool cloth was broadcloth weight, plain weave, obtained from Test Fabrics, Inc. The cotton cloth was Indian Head domestic broadcloth.

As Kreelon and Nacconol are the same type of detergent, namely an alkyl aryl sodium sulfonate, it would be expected that similar results would be obtained with them, and it will be observed from Table III that this is the case, except with nylon, where the copolymer gave considerably more improvement with Nacconol than with Kreelon. In the case of cotton, with the detergents, great improvement was brought about by the use of carboxymethylcellulose, and approximately the same improvement by the use of the copolymer; with soap some improvement was brought about by the use of sodium carboxymethylcellulose, and greater improvement by the use of the copolymer. in the case of nylon, both with the detergents and with soap, no improvement was brought about by the use of sodium carboxymethylcellulose, whereas great improvement was brought about by the use of the copolymer. In the case of cellulose acetate, with the detergents, a slight improvement was brought about by the use of sodium carboxymethylcellulose, and a great improvement by the use of the copolymer; with soap, which gave good results in the control, there was little change when either adjuvant was used. In the case of wool, both with the detergents and with soap, no improvement was given by the use of sodium carboxymethylcellulose, whereas moderate improvement was given by the use of the copolymer.

What we claim as our invention and desire to be secured by Letters Patent of the United States is:

l. A detergent composition comprising a detergent selected from the group consisting of the non-ionic detergents and the organic anionic detergents, and a copolymer of N-methylmethacrylamide and acrylonitrile, the copolymer having the structure wherein the ratio of n to m lies in the range of 9:1 to 7:3, and X=50 to 1000, the ratio by weight of copolymer to detergent being in the range from 1:99 to 25:75.

2. A detergent composition comprising a non-ionic detergent and a copolymer of N-rnethylmethacrylamide and acrylonitrile, the copolymer having the structure wherein the ratio of n to m lies in the range of 9:1 to 7:3, and X=50 to 1000, the ratio by weight of copolymer to detergent being in the range from 1:99 to 25:75.

3. A detergent composition comprising an organic anionic detergent and a copolymer of N-methylmethacrylamide and acrylonitrile, the copolymer having the structure 2,805,205 7 wherein the ratio of n to m lies in the range of 9:1 to 7:3, and X=50 to 1000, the ratio by weight of copolymer to detergent being in the range from 1:99 to 25:75.

References Cited in the file of this patent 5 UNITED STATES PATENTS 2,486,241 Arnold Oct. 25, 1949 8 FOREIGN PATENTS France Oct. 3, 1949 

1. A DETERGENT COMPOSITION COMPRISING A DETERGENT SELECTED FROM THE GROUP CONSISTING OF THE NON-IONIC DETERGENTS AND THE ORGANIC ANIONIC DETERGENTS, AND A COPOLYMER OF N-METHYLMETHACRYLAMIDE AND ACRYLONITRILE, THE COPOLYMER HAVING THE STRUCTURE 